Abstract

The low density limit k0 to the rate coefficient for tertiary association of ions and polar molecules is related through a double integral to an entity z1 or z2 that involves only the temperature, the reduced mass of the colliding pair, the polarizability and dipole moment of the neutral, and k(exp)[M], where k(exp) is the measured rate coefficient at ambient gas density [M]. The results are parametrized so that k0 may easily be found from laboratory data (irrespective of whether or not third order kinetics prevail).